The oldest rock found on Earth is a tiny zircon only micrometers in size and is 4.4 billion years old! The Earth is thought to have formed between 4.5 - 4.6 billion years ago so this rock has been around almost since the beginning of our planet.
The early Earth is thought to be a very chaotic landscape, something like this illustration by Steve Munsinger.
Through time there have been mass extinctions and the evolution of life building to the planet we live on today. So here is the geological timescale which all geologists go by when referring to a time period (Click on it to make it bigger).
The exact dates, names and eras of different times are constantly subject to change and can be updated should enough people agree on it.
But I bet you're wondering when life started, what were the big events and what do all of these bits represent? Well instead of writing a long list of when the most important bits of Earth's history was I have found a great youtube song which briefly covers the geological evolution of the Earth, so click the link below to find out more!